More than 10,000 relics, ____ between 5,000 to 3,000 B.C., ___ at Sanxingdui since it was first discovered.

A. dating back to, was dug up           B. dating back to, have been dug up

C. dated back to, has been dug up       D. dated back to, were dug up

实木地板背面对死节的要求是（）。

A.直径≦10mm个数不限

B.直径≦15mm个数不限

C.直径≦20mm个数不限

D.直径≦25mm个数不限